Ive got to -2±(sqrt)33/4 but dont know where to go from here.
And with the equation 2x=b^2-a^3b I need to make x the subject.
There are a couple of ways to do this, but I suspect you are looking for the use of the quadratic formula.
So for , a = 2, b = 3, c = -3. Thus:
For the other problem:
I don't know what you mean by "make x the subject." I am guessing you mean solve in terms of x?
This is a quadratic in terms of b. So using the quadratic formula again: